ash: Do not use MessageLoopForUI when not needed.

ash/display/display_manager.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ash/display/display_manager.h"
 
 #include <algorithm>
 #include <cmath>
 #include <set>
 #include <string>
@@ skipping 11 matching lines @@
 #include "ash/shell.h"
 #include "base/auto_reset.h"
 #include "base/command_line.h"
 #include "base/logging.h"
 #include "base/metrics/histogram.h"
 #include "base/run_loop.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_split.h"
 #include "base/strings/stringprintf.h"
 #include "base/strings/utf_string_conversions.h"
+#include "base/thread_task_runner_handle.h"
 #include "grit/ash_strings.h"
 #include "ui/base/l10n/l10n_util.h"
 #include "ui/gfx/display.h"
 #include "ui/gfx/display_observer.h"
 #include "ui/gfx/font_render_params.h"
 #include "ui/gfx/geometry/rect.h"
 #include "ui/gfx/geometry/size_conversions.h"
 #include "ui/gfx/screen.h"
 
 #if defined(USE_X11)
@@ skipping 1001 matching lines @@
   }
   return false;
 }
 
 void DisplayManager::CreateMirrorWindowAsyncIfAny() {
   // Do not post a task if the software mirroring doesn't exist, or
   // during initialization when compositor's init task isn't posted yet.
   // ash::Shell::Init() will call this after the compositor is initialized.
   if (software_mirroring_display_list_.empty() || !delegate_)
     return;
-  base::MessageLoopForUI::current()->PostTask(
-      FROM_HERE,
-      base::Bind(&DisplayManager::CreateMirrorWindowIfAny,
-                 weak_ptr_factory_.GetWeakPtr()));
+  base::ThreadTaskRunnerHandle::Get()->PostTask(
+      FROM_HERE, base::Bind(&DisplayManager::CreateMirrorWindowIfAny,
+                            weak_ptr_factory_.GetWeakPtr()));
 }
 
 scoped_ptr<MouseWarpController> DisplayManager::CreateMouseWarpController(
     aura::Window* drag_source) const {
   if (IsInUnifiedMode() && num_connected_displays() >= 2)
     return make_scoped_ptr(new UnifiedMouseWarpController());
   // Extra check for |num_connected_displays()| is for SystemDisplayApiTest
   // that injects MockScreen.
   if (GetNumDisplays() < 2 || num_connected_displays() < 2)
     return make_scoped_ptr(new NullMouseWarpController());
@@ skipping 333 matching lines @@
       gfx::Rect(new_secondary_origin, secondary_bounds.size()));
   secondary_display->UpdateWorkAreaFromInsets(insets);
 }
 
 void DisplayManager::RunPendingTasksForTest() {
   if (!software_mirroring_display_list_.empty())
     base::RunLoop().RunUntilIdle();
 }
 
 }  // namespace ash